Gaseous carbonitriding of high carbon chromium bearing steel: Correlation between composition, microstructure and stability

Gaseous carbonitriding of AISI 52100 steel was investigated under various processing conditions. The process parameters studied involve ammonia content (2.5–7.5 vol%), carbon potential (0.8–1.2%), and temperature (780–880 °C). carbon/nitrogen concentration-depth profiles that developed during were determined by light element analysis. microstructural residual stress evolution, the thermal-mechanical/dimensional stability, associated with dissolving nitrogen, reflected microscopy, X-ray diffraction, hardness indentation dimensional analysis, respectively. resulting concentration depth-profiles microstructure carbonitrided layer vary combination applied, thermodynamics. retained austenite state distribution stresses in specimen depend strongly on total (distribution) nitrogen dissolved surface layer. Carbonitriding leads to exceptional tempering resistance over conventional treatment (austenitization quenching), but results inferior stability due higher austenite.